Neurostimulation: Types, Benefits, Safety, and Effectiveness

Jun 4, 20246 min
different types of Neurostimulation - a detailed explanation

Our nervous system is like the control centre for all our physical and psychological functions. The nervous system is a complex system comprising of the brain, spinal cord, various nerves and neurotransmitters.

Neurostimulation, also called, neuromodulation, refers to various techniques and methodologies used for the modulation of the nervous system. These techniques and methodologies may be invasive, or non-invasive.

The aim of neurostimulation is to improve the quality of life of the individual. Neurostimulation has been used for conditions including chronic pain, epilepsy and treatment-resistant depression.  

What is a Neurostimulation Device?

A neurostimulation device is a medical device or equipment that is used to modulate nervous system activity. These devices may be invasive or non-invasive. These can be controlled and customized by the professional administering them. 

Some devices can also be controlled by the user themselves. The purpose of using neurostimulation is to break or change nervous system activity in order to prevent symptoms of the condition it’s aimed to treat. There is usually some fear or apprehension associated with neurostimulation. 

However, over the years, medical advances have led to methods and devices that are safe to use. We will talk more about the safety of neurostimulator devices in the section below. For now, let’s turn our attention to the types of neuristimulators that are commonly used. 

5 Types of Neurostimulators

types of Neurostimulators
Image Credit to ScienceDirect

1. Electroconvulsive Therapy (ECT)

Electroconvulsive treatment or ECT has been used for many years. While the associations with ECT spark images of painful ‘shock therapy’, this is not how it’s done in the present day. Present day devices allow safe and comfortable administration of ECT. ECT induces electrical pulses in the brain, which are shown to cause changes in brain functioning that can reverse symptoms of certain mental illnesses like severe depression, catatonia, dementia-related aggression and mania. 

2. Transcranial Magnetic Stimulation (TMS)

Transcranial magnetic stimulation or TMS is a non-invasive procedure used to treat symptoms of major depression, OCD and migraine. It is also used for smoking cessation. For all the conditions, it is used when other forms of treatment haven’t worked. TMS stimulates nerve cells in the brain using magnetic pulses that are transmitted by wrapping a coil around the skull. Usually, one requires multiple sessions to see the effect. 

3. Transcranial Direct Current Stimulation (tDCS)

Transcranial direct current stimulation or tDCS is a method used to improve cognitive and motor skills. Cognitive skills include learning, retaining and recalling information, decision making and problem solving. Motor skills refer to movement-related skills we need in order to perform our daily tasks.

It is a non-invasive method which has been used for behavioural modification and skill development in both, clinical populations as well as health populations. While in the clinical population, one can use tDCS to facilitate learning important cognitive, motor and social skills, in a healthy population, this method can help with enhancing performance. 

tDCS has also shown promising results for the treatment of depression, and anxiety. Some studies have also shown that tDCS can lead to symptom reduction in cases of OCD. Depression, anxiety and several other health conditions can adversely impact sleep. Trials show that tDCS can improve both, sleep quantity and quality, having an almost cascading impact on one’s overall well-being. 

Our very own wearable called ARC is a noninvasive neurostimulator which performs tDCS. We have conducted thorough studies for its use for depression, and found that with 30-minute usage for 21 days, around 65% of our users saw a reduction in symptoms of depression and anxiety

4. Vagus Nerve Stimulation (VNS)

Vagus nerve, or the vagal nerve bundle, is the main nerve of the parasympathetic nervous system. The parasymepathetic nervous system is responsible for ‘rest-and-digest’ response, which is the opposite of the ‘fight-or-flight’ state we enter when we are under stress. Vagus nerve stimulation isan invasive procedure, used for the treatment of cluster headaches, migrain and treatment-resistant depression. 

5. Deep Brain Stimulation (DBS)

Deep brain stimulation (DBS) is an invasive procedure which involves inserting electrodes in different areas of the brain. It’s used for movement-related disorders like Parkinsons’s and some psychiatric conditions such as OCD. Like other forms of neurostimulation treatments, DBS, too, is recommended if other forms of treatment, like medication, don’t work or have stopped working. 

5 Benefits of Neurostimulators

  1. Since technologies like tDCS do not have any known adverse side effects, they can be used as the first line of treatment for depression. 
  2. Our well-being is biopsychosocial - that is, it has a biological component, a psychological component and a social component. Neurostimulation addresses the biological component of many conditions 
  3. It can help alleviate symptoms and treat conditions where other forms of treatment have failed 
  4. In some pain-related conditions, it may help reduce dependence on medication 
  5. It can be a helpful form of treatment for several neuropsychiatric disorders in the elderly

What is Neurostimulation Therapy used for?

Neurostimulation therapy can be useful for a broad range of health conditions, including pain-related disorders, movement-related disorders, and certain treatment-resistant conditions such as depression, OCD, migraine and epilepsy. Since our well-being is more like a network rather than isolated symptoms, neurostimulation therapy can have a ripple effect on our overall well-being. 

Is Neurostimulation Therapy for You?

As it stands today, neurostimulation therapy is an FDA-approved course of treatment for several conditions. Whether it is suitable for you or not would depend on the history and severity of your condition, as well as the treatments that have already been undertaken. Your healthcare providers will be able to best guide you through the decision of whether or not you should opt for neurostimulation therapy.

Is the Neurostimulation Device Safe?

While invasive neurostimulation techniques come with the risks associated with surgery, non-invasive neurostimulation devices are generally considered safe, especially when used for a short period. 

Neurostimulation Side Effects

Like any form of treatment, neurostimulation, too, comes with the possibility of side effects. Depending on the type of neurostimulation, possible side effects may include mood changes, cognitive impairment, itching or burning sensation,  impaired memory, cough or hoarse voice. In invasive neurostimulation, there may be surgery-related risks and side effects such as infections, or injuries. 

While side effects may be more common in technologies such as ECT, where anaesthesia is given, newer neurostimulation technologies have minimal side effects. For tDCS in particular, the main side effect is skin irritation and related problems, and no other known side effects. 

Does Neurostimulation Work for Depression?

ECT, which is the oldest form of neurostimulation therapy in the field, has been shown to work well for severe or treatment-resistant depression.New methodologies of neurostimulation, including non-invasive procedures and wearables such as tDCS show promising results.

tDCS - Arc is a safe procedure with minimal side effects. With wearable devices, it also gives the patient more authority and control over how and when to use it. Additionally, with treatments such as tDCS, the probability of relapse of depression symptoms is reduced. Neurostimulation therapies offer us hope in the treatment of severe and treatment-resistant depression.  

References:

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Prachi Gangwani
Therapist | Yoga Teacher | Author of Dear Men: Masculinity and Modern Love in #MeToo India